On the slopes of the Ernesto Tornquist Provincial Park in the south of Buenos Aires province, there are fallow deer with red fur and white spots with webbed antlers that can reach 70 cm in length. They are not there by chance, there are no native fallow deer in the Americas.
Someone took them there and did so with the idea of ’fixing’ their grounds. What happened next is one of the most curious situations in the history of the world’s deer.
What are deer like you doing in the country? According to the CONICET reference sheet, it all properly began with Ernesto Tornquist. In 1905, this Argentine businessman brought fallen deer from Spain and Poland and released them at his home in the foothills of the Sierra de la Ventana. From there, and very quickly, they jump to many places. If the project had an almost landscape function in the beginning, hunting conservationists from all over the country quickly asked for samples and the situation got out of control. The dates vary, but it is clear that by the 1930s they had already been released into hunting reserves in central Argentina.
“Is he out of control”? I think that’s the right word, yes. In fact, since 2021, the fallow deer has appeared on the official list of invasive alien species in Argentina in the “controlled use” category. That is, you can hunt and breed, but with control. Be careful.
Today, he already lives freely in three provinces (Buenos Aires, Neuquen and Rio Negro). It is true that it is only found in abundance on Victoria Island and the Humul Peninsula; But that’s why we’re able to measure its true impact on ecosystems.
We already knew that, in Victoria, the deer nearly wiped out the maquis in the late 1980s. What we know today is that their feeding patterns (they selectively browse mountain cypress and other native woody plants) facilitate the invasion of other invasive species such as pine. Still on a smaller scale, ecosystems are slowly changing (replacing native species with European species).
An animal used for survival. And this is not the first time: these animals have to “conquer” or “recover” new ecosystems. In February 2024, a team of 45 researchers published PNAS The 10,000-year history of the European fallow deer and its conclusions were clear: with the Ice Age, only the species of roe deer, fallow deer, or fallow deer remained in any region other than the region around Anatolia and the Balkans.
In fact, we believe, all these animals returned to the Iberian Peninsula thanks to the Romans.
It’s natural, I say. The distinction between “native” and “invader” is much more tenuous than it seems. The fallow deer arrived in Barbuda around 1700 and became the national animal. Fallen deer in Argentina are still invasive, yes. But no one knows how long. And knowing their consequences on the environment, you have to ask yourself what to do sooner rather than later.
Picture | Diana Parkhouse
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